Note: This operation requires a spring compressor and new valve stem seals.
1. Lubricate the valve stems and insert them into the guide bushings in their original places. When installing new valves, insert them in the places where they were ground in.
2. Install the thrust washer.
3. Working on the first valve, dip the valve stem seal into fresh engine oil. New seals usually come with protective sleeves that should be placed on top of the valve stems to protect the seals from damage from the grooves under the keeper during installation. If the sleeves are missing, wrap a small amount of thin masking tape around the top end of the valve stem. Carefully place the seal on the valve stem and carefully slide it onto the guide sleeve. Be careful not to damage the seal as you slide it along the valve stem. Use a wrench or metal pipe to firmly seat the seals on the guide sleeves.
4. Install the valve spring onto the support washer, then install the upper spring plate.
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5. Compress the spring and insert two crackers into the groove on the valve stem. Release the spring smoothly, then repeat the steps for the other valves.
Tip: To prevent the crackers from falling out when releasing the spring, lubricate them with a small amount of grease.
6. After installing all the valves, place the head on a flat, hard surface and tap the valve stems with a hammer through a wooden spacer until all the parts are in place.
7. Where provided, install the thermostat housing onto the cylinder head.
8. Screw in the spark plugs where required.
9. Install the camshaft gear, valve lifters and camshaft as described in part A of this Chapter.
10. Install the intake and exhaust manifolds as described in Chapter 4.
11. Install the cylinder head as described in part A of this Chapter.
Six-cylinder petrol engines
12. Perform the actions described in paragraphs 1-8, inclusive.
13. Install the camshaft gear, valve lifters and camshaft as described in part B of this Chapter.
14. Install the intake and exhaust manifolds as described in Chapter 4.
15. Install the cylinder head as described in part B of this Chapter.
Diesel engines
16. Perform the actions described in paragraphs 1-7, inclusive.
17. If required, screw in the spark plugs as described Chapter 5.
18. Install the intake and exhaust manifolds as described in Chapter 4.
19. Install the cylinder head as described in parts of this Chapter.